Safety-gage



A. F. NAGLE.

SAFETY GAGE.

(No Model.)

No; 398,069. Patented Feb. 19, 1889.

ifi/7.1.

F TnNT AUGUSTUS F. NAGLE, OF CHICAGO, ILLINOIS.

SAFETY-GAGE.

SIJEGIFICATION forming part of Letters Patent No. 398,069,

dated February 19, 1889.

Application led October 20, 1888. Serial No. 283,703. (No model.)

To @ZZ whom it may concern:

Be it known thatI, AUGUSTUS F. NAGLE, of Ohicago, Illinois, have invented certain new and useful Improvements in Safety-Gages, of

which the following' is a specification.

'lhe main object of my invention is to provide an electric safety-gage apparatus which shall be complete in itself and ready for use by simply connecting it with the steam-boiler or other device to which it is to be applied.

Another object is to provide an electric contact in which the contact-points are brought together by an appreciable force as distinguished from those in which the contact is made by a needle moving over a dial in which the force is necessarily very light.

Other objects will be apparent from the structure of the apparatus and the subjoined description.

In the accompanying drawings I have represented a safety-gage containing my invention and set to operate at the upper limit of pressure.

In the drawings, Figure l is a perspective view of the complete apparatus, with the door of the battery-box removed to show the battery within. Fig. 2 is a sectional elevation showing the pressure-chamber, diaphragm, spring, and contiguous parts.

In the iigures, l is a box, stand, or bracket. 2 is the battery contained therein.

3 is anV electric bell.

4 is the part of the box in which the bellmagnet is contained.

5 is a pressure-chamber attached to the bracket.

G is a pipe through which communication is established between the steam-boiler or other device and the pressure-chamber.

7 is a flexible diaphragm in the upper part of the chamber.

8 is a post in the chamber to support the diaphragm against the'pressure of the spring above it. y

9 is a plunger attached to the diaphragm.

IO is a spring bearing down upon the plunger and contained in the tube ll.

l2 is a screw-cap, against which the upper end of the spring bears. By screwing the cap down or up the tension of the spring may be increased or diminished.

I3 is an arm connected to plunger 9, .so as to move with it, and II is a coiuact-lmint on the arm.

l5 is a contact-spring, against which point la is brought by the upward movement of plunger 0.

1G and 17 are connecting-wires.

IS is an index on tube ll to show the tension of the spring.

The lower edge of cap l2 may be also grad uated, so as to show the fractional parts of the divisions on scale 1S.

19 is an ordinarysteam-gage, which may be applied to my apparatus for comenience, but is not necessary to it, and as it forms no part of my invention I will not further describe it.

In operation, spring l0 having been adjusted to the required tension by the screwcap, the steam or other iluid under pressure enters chamber 5 through the pipe G and acts upon the under side of the diaphragm. IVhen its pressure rises to the safety limit at which the spring is set, and which is indicated by the index at 1S, the diaphragm and plunger 9 will be forced upward against the pressure of the spring and point li will be broughtin contact with spring l5, thus closing the electric circuit, and the bell will ring and call the attention of the attendant. The contactpoints being brought together by the direct pressure of the fluid on the diaphragm will not derange the apparatus, as would be the case if the contact were made through intermediate levers, hands, or needles, in which case the indications of the pressure would become unreliable and unsafe in their readings.

It is obvious that many structural variations and modifications may be made in this apparatus to suit the varying requirements in practice and still retain all of the advantages of the apparatus-snch as having' a device which is complete in its requiring only a single connection to put it in use, and such as having an appreciable force to bring the contacts together and close the circuit-and the other advantages of my invention; but such modification s and variationsvhcre made by the mechanic from his knowledge and skill, would not be a departure from the spirit of my invention.

What I claim isl. In an electrical pressure-indicator, the combination, with the chamber 5 andthe con- IOO tact-arm 15, of the shell l1,the movable plug 9, provided with a contact-point, 14, a spring, lO, bearing upon the plug, a diaphragm, '7, mounted in the chamber 5 and adapted to actuate the plug, which is independent of the diaphragm, a pipe, 6, adapted to convey fluid to the chamber beneath the diaphragm, and electric connections, all arranged for operation substantially as shown.

2. In an electrical pressure-indicator, the

combination, with the chamber 5 andthe contactarm l5, of the shell 11, provided with a spring, 10, a diaphragm, '7, mounted in the chamber 5, a plug, 9, provided With a contactpoint, 14, and resting upon the diaphragm, a stem, S, adapted to support the diaphragm, and electrical connections. p

3. In an electrical pressure-indicator, the combination, with the hollow shell ll and the chamber 5 and diaphragm 7, of the movable plug 9, resting upon the latter and adapted to complete the circuit,a spring, l0, inserted.

AUGUSTUS F. NAGLE.

lVitn esses:

WM. S. BATES, MINNIE ROBINSON. 

